1. Field of the Invention
This invention relates generally to an automatic exposure release for a camera and, more particularly, to a method and apparatus for automatically capturing a plurality of images during a pan to create a panoramic image.
2. Description or Related Art
Panoramic photography dates back to the 1840's. The first panoramas, taken in the 1840s, were made by taking a series of daguerreotype images that could then be framed or hung side-by-side. The same approach was later used with tintypes and paper prints. By the late twentieth century, motorized cameras were being made specifically for panoramic photography. In one type, the lens swung while the film remained stationary. In another type, the camera rotated on a special tripod to “paint” the image on a moving sheet of film. One of the most famous of such cameras, the Kodak Cirkut camera was patented in 1904. It used large format film, ranging in width from 5″ to 16″ could produce 360-degree photographs measuring up to 20 feet long.
Today, there are a number of specialized panoramic cameras that create panoramas for both prints and on-screen use. However, the cost of these specialized cameras is generally prohibitively expensive for most consumers. Additionally, the irregularly large size of the negatives produced by these specialized panoramic cameras require special film developing services which are both rare and expensive.
Specialized panoramic cameras are not the only way to produce panoramas. The development of computer imaging software has enabled normal cameras to be used to create panoramic photographs. A conventional film or digital camera can be used to create a seamless panorama by carefully capturing a series of images (i.e., frames) around a single point of rotation, the optical center of the lens. After the series of frames are captured, the frames must then be digitized if they weren't taken with a digital camera. Once in digital format, the frames can be stitched together into a seamless view with special imaging software, such as Rounabout Logic's Nodestar, VideoBrush's Photographer, or Live Picture's Photo Vista.
As the frames are captured with a conventional or digital camera, the camera is panned a certain amount such that there is enough of a previous frame overlapping the current frame so that the software can subsequently match features in the two consecutive frames and register the scenes together. Tripod systems are available to aid in panning. Some tripods come with degree marks to guide the camera, or detents to secure the camera in place. The number of frames required is dependent upon the focal length, angle of view of the camera, and the camera's orientation (horizontal or vertical). Oftentimes calculations are required to assure that the appropriate number of frames are taken. Thus, capturing multiple frames that can be successfully stitched together requires a certain degree of understanding in addition to specialized equipment.
Finally, certain digital cameras also include a selectable “panoramic mode.” However, this mode just captures a band across the middle of a conventionally sized image, leaving unexposed bands at the top and bottom of the image area. In effect, this is no different than just cropping an image after it is taken.
These are significant obstacles to making panoramic photography more accessible and reliable. Therefore, a simpler, automated approach is desirable to make panoramic photography available to most consumers without special cameras, equipment or development processing.